Breaking story a mass stabbing at a high school just outside Pittsburgh. If she's -- -- tracking the latest right now Paula. And -- that suspect is in custody but not before stabbing as many as twenty people at a Pennsylvania high school. -- -- Here's one of the victims being taken out on a stretcher. As aerial footage shows students and evacuating and buses lined up -- that -- Mac Kay -- hear the attack happened early this morning around 7 eastern before classes had even started at Franklin high school located just east of Pittsburgh. Which is home to 12100 students eyewitness reports saying that lone suspect a student at Franklin high was running around stabbing people. And there was crying and screaming in the whole ways. My friend -- said. He just saw him running with a -- and -- many turned the corner there's some kids like holding their stomach with blood everywhere the whole the whole science wing was just. Chaotic and crazy. Frantic parents were told to -- at home. It's important that parents realized at the scene is contained. Your students there are here are saying she was -- as -- So -- get down here now. -- my wife -- or to get down there to get -- right away no little thing though -- to prepare was anything like this and the words can't describe. So that the town was. -- -- Investigators are looking into the motor above the lone suspect who was a student they are questioning him right now -- -- targeted or was it -- -- -- As for the injured we are told the victims are not just students those ages -- from fifteen all the way to sixty. Doctors describe some wounds as life threatening an already. Many heroic stories coming out ABC news learning that one female student -- another student's life at the scene. By applying pressure to her wounds.

This transcript has been automatically generated and may not be 100% accurate.

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